We measured the expression of EMT‐related proteins in ML264‐treated osteosarcoma cells (0.5, 1 or 2 μmol/L) and found that exposure to ML264 significantly down‐regulated the mRNA and protein levels of mesenchymal markers (N‐cadherin, vimentin, Snail, MMP9 and MMP13) and up‐regulated the levels of epithelial cell marker E‐cadherin, in a time‐ and dose‐dependent manner (Figure 4A,B). Here, MMP9 is linked to osteosarcoma.